CHAP. II.] DIGESTION IN THE LIVING STOMACH. 153 



and fine; crude and chymified; all intimately mixed, and circulating pro- 

 miscuously through the gastric cavity, like the mixed contents of a closed 



vessel, gently agitated or turned-" in the hand." "As the food 



becomes more and more changed from its crude to its chymified state, the 

 acidity of the gastric fluids is considerably increased, and the general con- 

 tractile force of the muscles of the stomach is augmented in every direction ; 

 giving the contained fluids an impulse towards the pylorus It is probable 

 that from the very commencement of chymification from the time that 

 food is received into the stomach until that organ becomes empty portions 

 of chyme are constantly passing into the duodenum through the pyloric 

 orifice, as the mass is presented at each successive revolution. I infer this 

 from the fact that the volume is constantly decreasing. This decrease of 

 volume, however, is slow at first; but is rapidly accelerated towards the 

 conclusion of digestion, when the whole mass becomes more or less 

 chymified. This accelerated expulsion appears to be effected by a peculiar 



action of the transverse muscles, or rather of the transverse band 



situated near the commencement of the more conical shaped part of the 

 pyloric extremity, three or four inches from the smaller end. In at- 

 tempting to pass a long glass thermometer tube through the aperture 

 into the pyloric portion of the stomach, during the latter stages of diges- 

 tion, a forcible contraction is first perceived at this point, and the bulb 

 is stopped. In a short time, there is a gentle relaxation, when the bulb 

 passes without difficulty, and appears to be drawn, quite forcibly, for three 

 or four inches, towards the pyloric end. It is then released, and forced 

 back, or suffered to rise again ; at the same time giving to the tube a 

 circular, or rather spiral motion, and frequently revolving it completely over. 

 These motions are distinctly indicated, and strongly felt, in holding the 

 end of the tube between the thumb and finger ; and it requires a pretty 

 forcible grasp to prevent it from slipping from the hand, and being drawn 

 suddenly down to the pyloric extremity. When the tube is left to its 

 own direction, at these periods of contraction, it is drawn in, nearly its 

 whole length, to the depth of ten inches : and when drawn back, requires 

 considerable force, and gives to the fingers the sensation of a strong suction- 



power, like drawing the piston from an exhausted tube These 



peculiar motions and contractions continue until the stomach is perfectly 

 empty and not a particle of the food or chyme remains; when all becomes 



quiescent again The peculiar contractions and relaxations, mentioned 



above, succeed each other, at regular intervals of from two to four or 

 five minutes. Simultaneously with the contractions there is a general 

 shortening of the fibres of the stomach. This organ contracts upon itself 



in every direction ; and its contents are compressed with much force 



During the intervals of relaxation, the rugae perform their vermicular 



actions, the undulatory motions of the fluids continue, and the alimentary 

 and chymous masses appear, revolving as before, promiscuously mixed, 

 through the splenic and cardiac portions 1 ." 



In quoting verbatim considerable portions of Dr Beaumont's vivid 

 and unique observations on his patient, St Martin, the Author does 

 so because the description gives some idea of the intensity of the 



1 Beaumont, Op. cit., p. 102 et seq. 



